/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.alibaba.jstorm;

import org.yaml.snakeyaml.Yaml;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;

public class LoadConfig {
    public static final String TOPOLOGY_TYPE = "topology.type";

    private static Map LoadProperty(String prop) {
        Map ret = null;
        Properties properties = new Properties();

        try {
            InputStream stream = new FileInputStream(prop);
            properties.load(stream);
            ret = new HashMap<Object, Object>();
            ret.putAll(properties);
        } catch (FileNotFoundException e) {
            System.out.println("No such file " + prop);
        } catch (Exception e1) {
            e1.printStackTrace();
        }

        return ret;
    }

    private static Map LoadYaml(String confPath) {
        Map ret = null;
        Yaml yaml = new Yaml();

        try {
            InputStream stream = new FileInputStream(confPath);

            ret = (Map) yaml.load(stream);
            if (ret == null || ret.isEmpty() == true) {
                throw new RuntimeException("Failed to read config file");
            }

        } catch (FileNotFoundException e) {
            System.out.println("No such file " + confPath);
            throw new RuntimeException("No config file");
        } catch (Exception e1) {
            e1.printStackTrace();
            throw new RuntimeException("Failed to read config file");
        }

        return ret;
    }

    public static Map LoadConf(String arg) {
        Map ret = null;

        if (arg.endsWith("yaml")) {
            ret = LoadYaml(arg);
        } else {
            ret = LoadProperty(arg);
        }

        return ret;
    }
}